Introduction to conic sections | Conic sections | Algebra II | Khan Academy

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  • เผยแพร่เมื่อ 14 มิ.ย. 2009
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    What are conic sections and why are they called "conic sections"?
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ความคิดเห็น • 202

  • @joelmorris214
    @joelmorris214 8 ปีที่แล้ว +359

    KHANic sections.

    • @superroydude
      @superroydude 7 ปีที่แล้ว +1

      XD, you beat me to it.

    • @MechaDragonX
      @MechaDragonX 7 ปีที่แล้ว +1

      Areeb Shahjahan beat both of you by two years!

    • @tennoskuum9632
      @tennoskuum9632 5 ปีที่แล้ว

      You stole my joke

    • @tonybaston3419
      @tonybaston3419 3 ปีที่แล้ว +2

      I just come here with the sole intention of making that joke

  • @khanacademy
    @khanacademy  15 ปีที่แล้ว +71

    Great to hear that. Maybe I can do a series of videos on why bones break and how they heal (dedicated to you of course!). Actually, that's a pretty good idea. Need to do the basic bio first to do the healing part.

    • @alibabaintelligence8281
      @alibabaintelligence8281 3 ปีที่แล้ว +3

      omgggg justin biebeeeeeeeeer

    • @kj123._.
      @kj123._. 3 หลายเดือนก่อน

      @@alibabaintelligence8281 what

  • @khanacademy
    @khanacademy  15 ปีที่แล้ว +44

    Still trying to work out how to arrange the plane and the cone to get that.

  • @pongman
    @pongman 15 ปีที่แล้ว +27

    Thank you Sal. I work in an orthopaedic office and everyday I send all the kids that come in, to your website. The moms and dads come back to thank me for the info. When I talk to the kids I ask them how their math is in school and they look at me and say, "well I passed!" and then there's a chuckle. I've become a hit for them because they leave with more than a cast.

  • @pigmentsonpapers1647
    @pigmentsonpapers1647 2 ปีที่แล้ว +8

    If only I had learnt from you Sir. I would have feared maths less and be fascinated by its beauty more. I now understand why some people's eyes have a glint when they talk about maths. Thank you for your contribution.

  • @loverofbeats
    @loverofbeats 13 ปีที่แล้ว +16

    you're an amazing teacher! thank you for your time, sounds like you truly have a passion for teaching :D

  • @KickinAss1000
    @KickinAss1000 7 ปีที่แล้ว +18

    Your comparison of the two dimensional plain representing a single cross section of a three dimensional object completely just changed my picture of geometry, thank you.

  • @pizzapleope6595
    @pizzapleope6595 ปีที่แล้ว +5

    this video is older than me and i still learned loads thanks man

  • @urielruss
    @urielruss 3 ปีที่แล้ว +4

    Dude you are amazing. If everyone learned math like this, we would have a world of geniuses. Thank :)

  • @Tehcarp
    @Tehcarp 15 ปีที่แล้ว +2

    It's one part talent and one part that he cares.
    A rare combination. Far too rare.

  • @hunterepicness4303
    @hunterepicness4303 2 ปีที่แล้ว +2

    Wow just realized this video is over 12 years old.... and thanks to this over-a-decade old video I for the first time finally understand those conic figures at the end. They always looked so complicated but I finally understand it now!

  • @raygodinez1501
    @raygodinez1501 8 ปีที่แล้ว +6

    most excellent! good explanation.

  • @norwayte
    @norwayte 15 ปีที่แล้ว +6

    Thanks for the relations between them. I'm looking forward for the different equations for the ellipse.... parameter.... polar.... etc. and how they relate to each other. You have the gift.

  • @abbybasile936
    @abbybasile936 9 ปีที่แล้ว +39

    ATTACK OF THE COLORED LINES!!

  • @Theoryclash
    @Theoryclash 12 ปีที่แล้ว

    Thank you so much.
    You can not understand how greatly thankful I am to for you, you're what we need in front of our classrooms and at our dining tables teaching kids things.
    Just, thank you.

  • @sahilcharniya7622
    @sahilcharniya7622 10 ปีที่แล้ว +3

    really great introduction :)

  • @linuxguru27
    @linuxguru27 ปีที่แล้ว +1

    wonderful explanation, I am programmer, and maths always attracts me, and i was rusty and checking what i studied 21 yrs ago, and wallah this explanation is clear, and i re-learned the things today.
    Thank you for such wonderful lesson.

  • @Waranle
    @Waranle 15 ปีที่แล้ว

    Everytime i open one of your videos, i learn something new... that is the joy of watching your videoz, Thank you Sal

  • @cinquain0
    @cinquain0 5 ปีที่แล้ว

    That video was amazing! Great job Sal

  • @spanishbeard9654
    @spanishbeard9654 10 ปีที่แล้ว +62

    At 2:30 you have a smiley face lol

    • @bryannguyen8440
      @bryannguyen8440 8 ปีที่แล้ว +1

      +aaron flores It is a tilted parabola. You are funny

    • @toshikudo
      @toshikudo 7 ปีที่แล้ว

      Spanish Beard awww

    • @cloudystaku
      @cloudystaku 3 ปีที่แล้ว

      hahahahaha this made me laugh

    • @user-ou8vd3of5v
      @user-ou8vd3of5v 3 ปีที่แล้ว

      Why does noone reply to any of the comments below?

  • @potatopumpkin6925
    @potatopumpkin6925 3 ปีที่แล้ว +1

    Thank you Sir! I graduated high school with your help!! Thankyouu

  • @galikazoid
    @galikazoid 15 ปีที่แล้ว +1

    thanks for doing what you do; mathematics is fascinating

  • @hai2410
    @hai2410 15 ปีที่แล้ว

    My favourite of all your videos so far. very well explained indeed

  • @MrOscher
    @MrOscher 12 ปีที่แล้ว

    Awesome video, very clear understanding at the end of it's ten minutes. Audio quality was superb.

  • @emoalexisemoful
    @emoalexisemoful 11 ปีที่แล้ว

    I would never pass without you Sal, thank you very much!!!!!!!!

  • @PapaGotSkills
    @PapaGotSkills 13 ปีที่แล้ว

    I wish I had you as a teacher, your brilliant

  • @Jakers2009
    @Jakers2009 15 ปีที่แล้ว

    Sal you really are amazing... I mean I'm sure there are some guys out there who do reasearch into things and work out complicated stuff but I'm not sure they understand things like you do.... and definately do not present or explain things as well...

  • @dianedavidson5283
    @dianedavidson5283 4 ปีที่แล้ว +2

    Yes, there really ought to be a cool 3D software that shows all this more clearly.

  • @protoname_
    @protoname_ 12 ปีที่แล้ว +1

    Thanks for the idea!

  • @nvjolley
    @nvjolley 11 ปีที่แล้ว +2

    I actually fell asleep your voice is so soothing.

  • @pongman
    @pongman 15 ปีที่แล้ว

    Oh you're too kind. It would be a neat idea and I'm quite certain some first year ortho resident would find it most appreciative to see this on You Tube as well as the kids who go on your website to learn how bones heal as well as break. I think you explained Wolf's Law in one of your physics videos.

  • @imishan100
    @imishan100 11 ปีที่แล้ว +1

    Thanks keep up the good work sir

  • @guyses4983
    @guyses4983 3 ปีที่แล้ว +1

    thx huge help for my class

  • @kennethdadedzi3796
    @kennethdadedzi3796 10 ปีที่แล้ว

    Great introduction

  • @AlphaCrucis
    @AlphaCrucis 15 ปีที่แล้ว +1

    Thank you for this. I'm trying to learn the topics I missed in High School to prepare for college this fall. Is this in a playlist yet? Which playlist would it be? Conics or precalc?

  • @Ghaiyst
    @Ghaiyst 12 ปีที่แล้ว

    That's beautiful! It's sad that most math teachers in high school are too exhausted and the students themselves are too lazy to emphasize the beauty of mathematical concepts. I wish I knew this before so that i could have truely understood conics and be able to pass the tests. Instead, my math teacher was nice enough in 11th grade to drop this test and signed me up for AP calculus AB for the next year. Well, now that I'm a freshman in college calculus 2 leveled,Iwishiknewthisearlier

  • @TheAnaisP
    @TheAnaisP 11 ปีที่แล้ว +5

    4:20
    smiley face :)

  • @yyourfacee
    @yyourfacee 13 ปีที่แล้ว +2

    your drawings are amazing

  • @luciusirving5926
    @luciusirving5926 5 ปีที่แล้ว

    Still helpful for an old video and this is better than all the math videos from 2006 and 2007.

  • @ace1cx3
    @ace1cx3 12 ปีที่แล้ว

    Thank you!!!!! Now that I have watched your videos I understand all of it!!!! I use your website too. :D

  • @adeedeedeetv
    @adeedeedeetv 13 ปีที่แล้ว +1

    My teachers motto this semester:
    Learn it yourself I am being fired for DUI!
    Joy.
    Thanks to you I learned conics and logarithms

  • @Mammothgravitybattles
    @Mammothgravitybattles 9 ปีที่แล้ว

    Very cool, orbits are great.

  • @Jtking3000
    @Jtking3000 15 ปีที่แล้ว +2

    well you learn something new everyday :)

  • @theholywand11
    @theholywand11 12 ปีที่แล้ว

    The funnest thing is i'm in pre-algebra and now i know and can look into the future :]

  • @PolyFranchesco
    @PolyFranchesco 6 ปีที่แล้ว

    "you don't do this in your algebra 2 class"
    I am actually using this video for a project in my algebra 2 class where we are doing exactly what you said we shouldn't XD

  • @karimkhan1312
    @karimkhan1312 9 ปีที่แล้ว +2

    thank u sir for excellent lecture

  • @JohnnyJohn12503
    @JohnnyJohn12503 11 ปีที่แล้ว

    Im currently learning this through BYU. this is much better

  • @asherjunaid7847
    @asherjunaid7847 7 ปีที่แล้ว

    pioneering e learning!

  • @LiinksGaming
    @LiinksGaming 5 ปีที่แล้ว +1

    Dude this video is still useful even after 10 years of when it was published

  • @VideoOfMike
    @VideoOfMike 15 ปีที่แล้ว +2

    YES!!!!!!!
    The canadian education system skipped THE ENTIRE CONIC SECTION on PURPOSE!!! and the SAT math II REQUIRES CONICS!!!!!!!!!!!!
    THANKS!!!!!!!!!!!!!!!!!!!!!!!!!!

  • @venkateshprasad0
    @venkateshprasad0 11 ปีที่แล้ว +1

    I guess you never heard of Khan Academy,just search for khanacademy on google and visit their website and browse through the entire collection of video lectures.

  • @jeevanadithya743
    @jeevanadithya743 3 ปีที่แล้ว

    Sir I like your video the way u do explain and make us understand, as a student I want to give you an suggestion please don't take it other way sir I thik your videos could be more clearly understandable if you add animations to it to explain concepts like conic sections and it would be ease for u too also to explain.😊

  • @autumnseptember1674
    @autumnseptember1674 2 ปีที่แล้ว +1

    You are amazing.🤓

  • @bxcraftplayz1386
    @bxcraftplayz1386 ปีที่แล้ว +1

    Thank you khan academy

  • @theideacove1
    @theideacove1 4 ปีที่แล้ว +1

    subtitled in 21 different languges. wow good job 👍

  • @orchidscion
    @orchidscion 5 ปีที่แล้ว +5

    Now I'm less likely to fail my test. I literally made a 0 on a quiz to to a lack of understanding

  • @harshathkanadka1672
    @harshathkanadka1672 3 ปีที่แล้ว

    Dude the best channel !!! 1000×better than byjus

  • @rajuthoppil3393
    @rajuthoppil3393 2 ปีที่แล้ว

    Awsm teaching

  • @denibarondo9277
    @denibarondo9277 5 ปีที่แล้ว

    I like your humor khan academy :))

  • @paulasarmiento9449
    @paulasarmiento9449 5 ปีที่แล้ว

    i learn more from this channel than i do from my school teacher

  • @gerardo0100
    @gerardo0100 11 ปีที่แล้ว +1

    thank you

  • @SOLOVEFUCKINGmuz
    @SOLOVEFUCKINGmuz 13 ปีที่แล้ว +1

    @weurRTG Thanks, I'm 17, in Quebec we learn this in the equivalent of I don't know how it works, somewhere in high school maybe, and it think it's really hard.

  • @theweirdosyeah
    @theweirdosyeah 12 ปีที่แล้ว +6

    Haha, 4:17 there's a smily face :)

  • @pami7160
    @pami7160 2 ปีที่แล้ว

    12 years ago but I need this experience now

    • @pmdchi
      @pmdchi 2 ปีที่แล้ว

      lol

  • @getsurasengan
    @getsurasengan 13 ปีที่แล้ว

    I learned alot

  • @divyasharma6389
    @divyasharma6389 11 ปีที่แล้ว

    thnx good explanation

  • @Jakers2009
    @Jakers2009 15 ปีที่แล้ว

    Thats so true, but i still understand it all... once the jargon is outta the way..

  • @Irades
    @Irades ปีที่แล้ว

    Thank you :)

  • @beeayyee9977
    @beeayyee9977 6 ปีที่แล้ว +1

    Write down an outline for your video, will help with guessing what to explain next.

  • @DeSanctist
    @DeSanctist 11 ปีที่แล้ว

    yeah, correct! us too.

  • @efcc123
    @efcc123 2 หลายเดือนก่อน

    Reviewing conics for central force :3

  • @shatilachowdhury5321
    @shatilachowdhury5321 5 ปีที่แล้ว

    Thank you for this video. I am taking precalculus in college. It really helps. Thanks again, Sal Khan, Khan Academy

  • @aneeshaph5007
    @aneeshaph5007 3 ปีที่แล้ว

    Thankyou

  • @MrShasheem123
    @MrShasheem123 11 ปีที่แล้ว +1

    Exercise in 3-d drawing!! :D XD

  • @DefaultGray
    @DefaultGray 9 ปีที่แล้ว +10

    Smiley face!

    • @PAWNB3YOND
      @PAWNB3YOND 4 ปีที่แล้ว +1

      Yelling facial expressions is not how facial expressions work

  • @invisiblebutterfly6
    @invisiblebutterfly6 12 ปีที่แล้ว

    What if you put the plane completely vertical and in the centre of the cone? Is the result of that an absolute value graph...or am I just confusing myself now?
    Nice video btw! :)

  • @pyrojayxx1366
    @pyrojayxx1366 3 ปีที่แล้ว

    I love you sir.

  • @shastacon45
    @shastacon45 7 ปีที่แล้ว +2

    jajajj you drew a smiley face

  • @amadodiego88
    @amadodiego88 11 ปีที่แล้ว +1

    2:14 happy face

  • @bninjabninja
    @bninjabninja 12 ปีที่แล้ว

    Check this out! This video has a Download button in the description !!!

  • @lemayanelisha9867
    @lemayanelisha9867 10 ปีที่แล้ว

    Thanks thanks thanks

  • @BlackOpsIsTheBest
    @BlackOpsIsTheBest 11 ปีที่แล้ว

    Everyone from Teague and Anderson, this is pretty good stuff! Better hope we don't end up chasing this down with 8 sections of notes though. XD Have a great day everyone!
    #p.4 teauge? nah #'s too lame
    Baylife

  • @wesleyondisdike9647
    @wesleyondisdike9647 3 ปีที่แล้ว +1

    Wow, this was before khan academy was even a thing, this was the beginnings when sal was alone, ig that's why the software and video quality is low

  • @Heartfulnesss
    @Heartfulnesss 9 ปีที่แล้ว +1

    define focus?

  • @dreaming_of_that_mbbs_mbchb
    @dreaming_of_that_mbbs_mbchb 9 ปีที่แล้ว +3

    Can u link previous videos please also using all maths on khan webpage how long is that going to take as takeb 5 days and only learnt 20 skills

  • @lanaashraf5106
    @lanaashraf5106 5 ปีที่แล้ว

    The parabola should've been drawn as a line in the planar view, not a curve, since the plan you're cutting with is perpendicular to the plan view.

  • @weurRTG
    @weurRTG 13 ปีที่แล้ว

    @SOLOVEFUCKINGmuz Algebra II is usually taught at age 15, or 10th grade. However, I've seen 11th grade students take the course, and I've even seen 8th graders take the course.
    I took it as a 9th grade student.

  • @trecool212
    @trecool212 12 ปีที่แล้ว

    The line and point are both conic sections as well, yes?

  • @nashidragneel7776
    @nashidragneel7776 5 ปีที่แล้ว +1

    Prrrrraabola!!

  • @j2ultimatefan
    @j2ultimatefan 11 ปีที่แล้ว

    when he started the 3D drawing I kept moving my head right and left without even noticing lol XD

    • @shellssoul
      @shellssoul 4 ปีที่แล้ว

      @Lady Oscar lol GOD BLESS ❤️✨😂🙏🏽

  • @abrarshezad102
    @abrarshezad102 7 ปีที่แล้ว +1

    i am watching it in 2017

  • @emoalexisemoful
    @emoalexisemoful 11 ปีที่แล้ว +1

    2:21 looks like a smiley..

  • @bluerose83092
    @bluerose83092 11 ปีที่แล้ว

    studying for my upcoming midterm and then my final...i hope i do well! :/

    • @flidict-8490
      @flidict-8490 4 ปีที่แล้ว

      bluerose83092 well...did you do well?

  • @sirhawkings
    @sirhawkings 10 ปีที่แล้ว

    PARABOLA ANR CIRCLES

  • @tuhindey5022
    @tuhindey5022 9 ปีที่แล้ว +1

    Hey the formulas for parabola are not y = x^2 and x = y^2.....But they are x^2 = 4ay and y^2 = 4ax.....

    • @bryannguyen8440
      @bryannguyen8440 8 ปีที่แล้ว

      +tuhin Dey Well, if I had to comment, yeah it looks right

  • @MrHjld
    @MrHjld 11 ปีที่แล้ว

    10:52 ... wow

  • @waterlily716
    @waterlily716 15 ปีที่แล้ว +6

    is an ebola a conic section? hee hee
    ah thanks for this video. good old algebra two :)

    • @bhavikaagarwal_
      @bhavikaagarwal_ 4 ปีที่แล้ว

      Oh my god.. seriously!!!?

    • @jordyvillanueva7325
      @jordyvillanueva7325 4 ปีที่แล้ว

      Hello ! 10 years ago

    • @hexa3389
      @hexa3389 3 ปีที่แล้ว

      Ebola joke 10 years ago...
      Is Corona a conic section?

  • @orangegold1
    @orangegold1 14 ปีที่แล้ว

    So is a point a conics section... if your plane is horizontal right in the point that the two tips of the cones meet?

  • @imanengineer1674
    @imanengineer1674 4 ปีที่แล้ว

    ❤❤

  • @netraraman4532
    @netraraman4532 8 ปีที่แล้ว

    Sir I have a question: wasn't that parabola one intersecting the above cone (the one which was parallel ) so won't it will actually become a hyperbola?

    • @samgaines2337
      @samgaines2337 8 ปีที่แล้ว +1

      +Netra raman You're just viewing it wrong. If it's parallel, it will never cross.